Author Topic: want to improve fender blues junior (Read 10489 times)

Dave_M · « **on:** April 29, 2008, 08:39:02 PM »

Does anyone have a blues junior? What do you think of it?

I have one. it's a good amp and a lot better than the marshall it replaced, but needs improving. Main gripes with it are it can be really bright (with a harsh quality). And also has a major problem with resonance with the A note (like 12th fret A string is pretty bad). Generally I have to turn it down or it can give me a headache. And that's not much fun lol.

I want to make the blues junior a really nice clean amp like fender twin reverb. So I need to reduce bias for more headroom and also improve the tone controls as well. Also thinking of changing the speaker in it to maybe a celestion blue (bit expensive though). If I do that maybe it will sound better than twin reverb. Worth trying or better to get a different amp do you think?

sgmypod · « **Reply #1 on:** April 29, 2008, 09:42:46 PM »

watford valves do a few upgrades think main one is the speaker...to a warmer better alrounder

Kilby · « **Reply #2 on:** April 29, 2008, 09:46:27 PM »

The mods from BillM are pretty good and he is also very helpful (well he helped me out anyway)

Try here http://home.comcast.net/~machrone/bluesjunior.htm for a start

Rob...

Elliot · « **Reply #3 on:** April 29, 2008, 09:59:52 PM »

I have a Blues Junior modded to hell and I love it. I run it either with a Eminence Texas Heat or through a G12H 2x12 cab and it is a real blaster of an amp.

The first fix is to reduce the V1 tube from a 12AX7 to a 5751 or a 12AT7. I know people are pretty macho on these boards about gain, but the 12AX7 at V1 floods too much gain into the pre-amp circuit making it harder. I use 3 GE 5751s for my tubes which retain a good overdrive response but allow you to use pedals without things turning to mush.

The BillM mods are easy - I have most of BillM's mods -
http://home.comcast.net/~machrone/bluesjunior.htm

His cable dress mod is easy and really takes some of the problem of some of the A note oscillation.

You could do the twin stack mod without removing the board if you have a soldering iron. The ability to dial out the middle control totally allows you much better cleans - its a real revelation on the tone of the amp. The power supply stiffening mod cures the A note resonance and also improves the bass response and can be done in less than ten minutes without taking the board out.

The other PCB mods are easy but removing the board itself is an utter bitch - it takes lots of careful patience. The bass response is improved by the tone stack mod - in fact the amp ceases to be Fender bright when you've done them all and you have a great tone.

Once you've done them all - the BJ has great grunt and great bass response - things like the presence control mod and the clean boost have to be bought from Bill and are a bit tricky.

The Hammond 1750H output transformer is directly compatible and also gives more power - but you do have to drill a hole in the PCB (a non printed part).

As to speakers - I wouldn't bother with an Alnico Blue - its too light a speaker: Fender are notorious for their wattage to be based on clean sound which means that a 15 watt speaker in a 15 watt Fender is likely to blow. The best speakers for this amp in my view and the opinion of most modders of this amp is the Eminence Texas Heat followed by a broken in G12H30 - The Texas Heat improves the bass response, the warmth and produces a break up that is sympathetic with the amp.

Dave_M · « **Reply #4 on:** April 30, 2008, 12:31:38 PM »

Eminence Texas Heat looks like a real jem! Thanks. I will try some of the BillM mods too.

I don't think my amp is oscillating. I just tryed that A not resonance again and it's really bad. It's like a deep sub bass that swamps the guitar playing and shakes the house - even though I don't have the amp that loud. I'll try the PSU stiffening like you suggested. Hopfully that will fix it.

Do you know what fender did to make the 2nd version of the blues junior so bright? I can't have the treble above 3 and even turned all the way down it doesn't go away completly. But I'm hoping the BillM tone mods will fix that as well.

Elliot · « **Reply #5 on:** April 30, 2008, 01:16:48 PM »

Try dressing the power cables as billM says - its a less than 5 minute job and when I did it I lost some of blurriness on bass notes.

As to the brightness - Its the new design in general, not one component - do all the BillM mods at one sitting - especially the power supply stiffening mod (email bill for this - its very simple but as its not on his website I don't want to steal his thunder), the twin stack and the tone stack mods and people will be telling you to turn the treble up!

btw is yours the Tweed with a Jensen C12N? - if so that speaker heightens the brightness, its not a very good speaker for the Blues Junior for more modern sounds.

If you want I could do some speaker examples - what guitar do you play so you I can in the near zone to your set up?

Dave_M · « **Reply #6 on:** April 30, 2008, 01:47:45 PM »

Yea speaker examples would be really great thanks! Mine is a standard black blues junior. My guitar is a strat with apaches and a 1 piece maple neck (maybe that adds to the brightness?)

Elliot · « **Reply #7 on:** May 02, 2008, 05:08:00 PM »

Dave I puts some hastily jammed blues junior clips of difference speakers in the players part